MySQL选择特定的行值作为列名

SELECt a.ID,
a.Campaign_ID,
a.FirstName,
a.LastName,
MAX(CASE WHEN b.data = ‘qwerty1’ THEN b.Name END) qwerty1,
MAX(CASE WHEN b.data = ‘qwerty2’ THEN b.Name END) qwerty2,
MAX(CASE WHEN b.data = ‘qwerty3’ THEN b.Name END) qwerty3
FROM Participants a
INNER JOIN Participants_Custom b
ON a.ID = b.Participant_ID
GROUP BY a.ID,
a.Campaign_ID,
a.FirstName,
a.LastName

• SQLFiddle演示

更新1

由于的值

data

SET @sql = NULL;SELECt  GROUP_CONCAt(DISTINCT    CONCAt(      'MAX(CASE WHEN b.data = ''',      data,      ''' THEN b.Name ELSE NULL END) AS ',      CONCAt('`',data, '`')    )  ) INTO @sqlFROM Participants_Custom;SET @sql = CONCAt('SELECt  a.ID,     a.Campaign_ID,     a.FirstName,     a.LastName,', @sql,        'FROM     Participants a      INNER JOIN Participants_Custom b          ON a.ID = b.Participant_ID         GROUP   BY  a.ID,          a.Campaign_ID,          a.FirstName,          a.LastName');PREPARE stmt FROM @sql;EXECUTE stmt;DEALLOCATE PREPARE stmt;

• SQLFiddle演示